Maintain or restore hydrology

EASTERN: Projected changes in precipitation and temperature are expected to alter hydrologic regimes through changes in streamflow, snowpack, evapotranspiration rates, soil moisture, surface runoff, infiltration, flooding, and drought. Hydrologic changes could occur gradually or rapidly through extreme events. Some ecosystems are very susceptible to stress from drought, which may increase in frequency, severity, duration, or extent as a result of changing precipitation patterns. Other ecosystems are susceptible to flooding and ponding. Maintaining sufficient water levels and flow patterns is critical to ecosystem function. Hydrology can be altered by infrastructure (e.g., dams, roads, and other impervious surfaces), excessive groundwater extraction, stream channelization, and even invasive plants. Existing infrastructure that diverts water, or otherwise alters hydrology, may need to be reevaluated to compensate for changes in water levels or flows. Infrastructure will also need to be designed to accommodate greater hydrologic extremes in the future. It is important to keep in mind that modifications to maintain hydrology at one site may have negative impacts on hydrology at another site. 

WESTERN: Projected changes in precipitation and temperature are expected to alter hydrologic regimes through changes in snowpack, streamflow, evapotranspiration rates, soil moisture, surface runoff, infiltration, flooding, and drought. Hydrologic changes could occur gradually or rapidly through extreme events. Some ecosystems are very susceptible to stress from drought, which is increasing in frequency, severity, duration, and geographical extent as a result of these changes in the hydrologic cycle and the effects of human water uses, such as irrigation. Other ecosystems are susceptible to flooding, ponding, or high-water tables as storm intensities increase. Maintaining sufficient water levels and flow patterns is critical to ecosystem function, and the survival of fish and other aquatic species. Hydrology can be altered by infrastructure (e.g., dams, roads, and other impervious surfaces), excessive groundwater extraction, soil compaction, stream channelization, and even invasive plants. Existing infrastructure that diverts water, or otherwise alters hydrology, may need to be reevaluated to compensate for changes in water levels or flows. Infrastructure will also need to be designed to accommodate greater hydrologic extremes in the future. It is important to keep in mind that modifications to maintain hydrology at one site may have negative impacts on hydrology at another site. In places where hydrology has been altered by agricultural land uses, restoration actions can include managing the impacts of cattle and other grazers on streams, and using structures or berms to slow water flow and moderate the impacts of soil compaction and river channelization.

Climate change will have substantial effects on a suite of ecosystem functions, such as carbon storage, nutrient cycling, wildlife habitat, hydroelectric generation and water provisioning. As a result, many management actions will need to work both directly and indirectly to maintain the integrity of ecosystems in the face of climate change. This strategy seeks to sustain fundamental ecological functions, especially those related to soil and hydrologic conditions.